Mybatis-plus学习

Mybatis-plus学习

自动填充功能

1. 实体类字段添加注解

   package com.hw.mpstart.entity;
   
   import com.baomidou.mybatisplus.annotation.*;
   
   import java.io.Serializable;
   import java.math.BigDecimal;
   import java.time.LocalDateTime;
   import io.swagger.annotations.ApiModel;
   import io.swagger.annotations.ApiModelProperty;
   import lombok.Getter;
   import lombok.Setter;
   
   /**
    * <p>
    * 
    * </p>
    *
    * @author 黄伟
    * @since 2022-10-14
    */
   @KeySequence(value = "SEQ_JTEST")
   @Getter
   @Setter
   @TableName("J_TEST")
   @ApiModel(value = "JTest对象", description = "")
   public class JTest implements Serializable {
   
       private static final long serialVersionUID = 1L;
   
       @ApiModelProperty("名称")
       private String name;
   
       @ApiModelProperty("密码")
       private String pw;
   
       @ApiModelProperty("备注")
       private String remark;
   
       @ApiModelProperty("主键")
       @TableId
       private String id;
   
       @ApiModelProperty("创建日期")
       @TableField(fill = FieldFill.INSERT)
       private LocalDateTime createTime;
   
       @ApiModelProperty("修改日期")
       @TableField(fill = FieldFill.INSERT_UPDATE,update = "sysdate")//自动填充注解
       private LocalDateTime modifyTime;
   
       @ApiModelProperty("默认值")
       @TableField(fill = FieldFill.INSERT)//自动填充注解
       private String defual;
   
       @ApiModelProperty("版本号")
       @TableField(fill = FieldFill.INSERT)
       @Version
       private Integer version;
   
       @ApiModelProperty("是否删除")
       @TableField(fill = FieldFill.INSERT)
       @TableLogic
       private BigDecimal isdelete;
   
   
   }
   
   

2. 添加处理器类

   package com.hw.mpstart.handler;
   
   import com.baomidou.mybatisplus.core.handlers.MetaObjectHandler;
   import lombok.extern.slf4j.Slf4j;
   import org.apache.ibatis.reflection.MetaObject;
   import org.springframework.stereotype.Component;
   
   import java.math.BigDecimal;
   import java.time.LocalDateTime;
   
   @Slf4j
   @Component
   public class MyMetaObjectHandler implements MetaObjectHandler {
       @Override
       public void insertFill(MetaObject metaObject){
           log.info("start insert fill ...");
           this.strictInsertFill(metaObject, "createTime", LocalDateTime.class, LocalDateTime.now());
           this.strictInsertFill(metaObject, "modifyTime", LocalDateTime.class, LocalDateTime.now());
           this.strictInsertFill(metaObject,"defual",String.class,"默认值");
           this.strictInsertFill(metaObject,"version", Integer.class,1);
           this.strictInsertFill(metaObject,"isdelete",BigDecimal.class,new BigDecimal(0));
   
       }
       @Override
       public void updateFill(MetaObject metaObject){
           log.info("start update fill ...");
           this.strictUpdateFill(metaObject,"modifyTime",LocalDateTime.class,LocalDateTime.now());
       }
   }
   
   

3. 使用乐观锁导致时间无法自动更新解决办法

    @TableField(fill = FieldFill.INSERT_UPDATE,update = "sysdate")//实体类字段注解添加update = "sysdate",其中sysdate是对应数据库类型的系统日期获取方法